JPH07508492A - Glass composition and its manufacturing method - Google Patents

Abstract

A neutral, generally green colored, infrared energy and ultraviolet radiation absorbing glass composition comprises conventional soda-lime-silica float glass ingredients, a relatively high concentration of moderately reduced iron, and titanium oxide(s). The resultant glass exhibits an Illuminant A visible light transmittance of at least 70%, a total solar energy transmittance not greater than about 46%, and an ultraviolet radiation transmittance not greater than approximately 38%, at selected glass thicknesses in the range of 3mm to 5mm. The titanium oxide(s) as well as at least a portion of the iron in the glass is provided by the inclusion of the mineral ilmenite in the glass batch formulation.

Description

[Detailed description of the invention] Glass composition and its manufacturing method Lu's back 1 Product 1 The present invention uses ultraviolet and infrared absorbing soda lime silica containing iron and titanium oxides. glass (soda-1ime-s 11ica glass) composition and this glass The present invention relates to methods of making glass compositions and also methods of making glass products therefrom. Special In addition, the present invention provides a neutral, usually green colored material with specific energy absorption and light transmission properties. The present invention relates to glass compositions. Preferably, suitable glasses according to the invention have a narrow range of It has a dominant wavelength and color purity. The present invention has high visible light transmittance and total solar energy For the manufacture of automobile and architectural window materials that require low energy transmittance and low ultraviolet transmittance. Particularly useful for construction.

subjugation technique As is generally known, soda lime silica glass, which absorbs heat and infrared rays, It can be produced by adding iron. Iron is usually oxidized within the glass. It exists as iron (FeO) and ferric oxide (Fezes). Ferrous oxide and oxidation The degree of ferric content has a direct and important effect on the color and light transmission properties of the glass. give. By chemically reducing ferric oxide, the content of ferrous oxide increases. When added, the absorption rate of infrared rays also increases and the absorption rate of ultraviolet rays decreases. To Fezes When the concentration of FeO is increased, the color of the glass changes from yellow or yellow-green to dark green. The color changes to a blue-green color, and the transparency of visible light becomes poor. Therefore, the transmission of visible light In order to increase the absorption of infrared rays in glass without making it a host, it was necessary to Produces glass with low content and highly reduced Fezes to FeO It has been considered necessary to do so.

U.S. Patent No. 2,860,059 discloses that the overall iron concentration is kept low. Additionally, ultraviolet absorbing glass compositions are disclosed. According to the statement, this The glass composition is a greenish-blue color commonly used as automotive and architectural window materials. Superior visible light transmittance compared to glass.

In order to maintain colorlessness and high visible light transmittance in this glass, the iron concentration is kept at a minimum. Even if it is large, it is 0. It is 6% by weight.

This glass is coated with titanium oxide and O. 5% by weight The following cerium oxide is added.

U.S. Pat. No. 1,936.231 discloses that ferric oxide is used as a UV blocker. A colorless glass doped with is disclosed. The amount of ferric oxide is small and The glass has high visible light transmittance. Approximately 0.035 weight as the total concentration of iron % is recommended. This patent specification further includes a glass assembly with a low iron content. It has been disclosed that a cerium compound is added to the composition as an ultraviolet blocking agent. There is. Thereby, the obtained glass composition maintains colorlessness and has a high potency. It also has visual light transmittance.

U.S. Pat. No. 4,792,536 states that although the overall iron concentration is low, FeO A method for manufacturing infrared energy absorbing glass containing highly reduced iron is disclosed. ing. Furthermore, by increasing the overall iron content in the glass composition, infrared It has been disclosed that energy absorption can be increased; Visible light transmittance deteriorates due to this, and it is considered to be sufficient as a window material for automobiles. It is also stated that it can be below the level. The disclosed manufacturing method consists of two stages. Melt refining method (a two stage melting and refining method) g operation) to generate a state that highly promotes reduction, and to increase the concentration. is between 0.45% and 0.65% by weight of ferrous oxide throughout the iron. Increase the proportion of iron in According to this patent, the content of iron is small. At least 35% must be reduced to FeO.

Most preferably, 50% or more of the total iron contained is reduced to the state of ferrous oxide. That is. Furthermore, according to what is disclosed in this patent specification, ultraviolet ray absorption In order to improve the iron content, 0.25% to 0.5% by weight of cerium oxide is added to the total iron concentration. It is added to glass compositions where the iron content is kept low and the iron content is highly reduced. Good too. A certain amount of TiO2, ■,06, to M　o　Os may be added.

U.S. Patent No. 5,077.133 discloses that cerium oxide is used as an ultraviolet absorber. A green heat-absorbing glass is disclosed. Another embodiment of this patent includes A portion of the cerium oxide produced is replaced by an amount of TiOs. This moth The overall iron concentration of the lath composition is relatively high, with 0. 7% to 1.25% by weight It's between.

Ehada summer alliance According to the invention, a neutral, typically green glass composition having a thickness of about 3 mm to 5 m m, the visible light transmittance by light source A is at least 70%, and the total The transmittance of solar energy is about 46% or less, and the transmittance of ultraviolet rays is about 3 Glass compositions are provided that are 8% or less, preferably about 36% or less. here, The thickness of the glass can be determined by whether it is made of a single piece of glass or made up of multiple glass sheets. In any case, even if the total thickness is within the indicated range. Please understand that this indicates the value of Also disclosed herein The light transmittance was evaluated for the following wavelength range: UV 30 0nm~400nm Visible light 400nm ~ 770nm Total sunlight 300nm ~ 2130nm This glass composition contains a glass based on soda lime silica and is a major Furthermore, about 0.4% to 0.9% by weight of Fe2Om and 0.1% by weight are added as components. Amount % - 0.5% by weight of FeO and 0.25% by weight to 1. 25ffi amount% Tl Contains a coloring agent consisting of O2. These glasses are approximately 495 nm to 5 by light source C. It has a dominant wavelength of 35 nm and a color purity of about 2% to 5%. This kind of glass is Batch compositions in which the concentration of total iron present in the form of Fezes is greater than about 0.45% ( batch compositions). Here, the glass industry Then, the total iron contained in the glass composition or batch (total 1ron) is It is common to express it as "the entire iron expressed as Fe5O3". glass bag When iron is melted, some of the iron content is reduced to FeO, but the rest is FeO. *Remains Os. The concentration balance of ferrous oxide and ferric oxide in molten glass is Determined by the equilibrium between oxidation and reduction reactions, in this specification, including the claims, It is expressed as a "ferrous oxide value". Fe2Om By reducing, not only FeO but also oxygen gas is generated, resulting in glass products. The combined weight of the ferrous oxide and ferric oxide inside decreases. Therefore, the resulting galaxies The actual combined weight of FeO and FezO- contained in the gas composition is Fe20g. It is lighter than the weight of the entire batch of iron expressed as . For this reason, “the whole iron” or “the whole iron expressed as Fe20-” in the present specification including the claims, It is to be understood that it means the total weight of iron contained in the glass batch before being reduced.

Furthermore, as will be understood, "ferrous oxide value" is used herein, including in the claims. is the weight percent of ferrous oxide in the resulting glass, based on the total iron expressed in Fezos. Defined as the value divided by weight percent.

The glass composition according to the invention is particularly suitable for the production of infrared energy and ultraviolet absorbing glasses. This type of glass is used as window material for automobiles and architecture. . Therefore, glass sheets made from this glass composition can be heat-strengthened or tempered. or, conversely, annealed, with a material such as polyvinyl butyral in between. It is sometimes made into a layered structure, including a layer of transparent resin, and is used, for example, as a windshield. General Usually, the thickness of the windshield glass plate is about 1.7 mm to about 2.5 mm, and it is used for side lights and back lights. The thickness of the glass plate adjusted and used as a lamp is approximately 3 mm to approximately 5 mm.

Unless otherwise specified, % refers to % by weight in this specification, including the claims. wave Wavelength dispersion X-ray 　flu.

The weight of the entire iron expressed as Ti0z or Fe2Og using %It was determined. To determine the overall reduction rate of iron, we first used a spectrophotometer to The transmittance of the sample at a wavelength of 11060n was measured. Next, 1106 Optical density was calculated using the following formula using the transmittance for a wavelength of 0n: Optical density = L o g to (T/To) where To is from 100 to The value obtained by subtracting the evaluated loss rate from emissivity = 92, T is for the wavelength 11060n This is the transmittance. In this way, the reduction rate was calculated using the optical density. Refund rate =110x optical density/(glass thickness x total iron weight%) where the unit of glass thickness is is mm, and the weight percent of the total iron is the weight percent of the total iron expressed as FC'zO* .

Brief description of the drawing When used in automobile windshields, infrared energy and ultraviolet absorbing glass meet national standards. In other words, the visible light transmittance to the light source must be greater than 70%. It is necessary to have a high level of performance. The glass used in modern cars has become thinner. , it became easy to reach 70% transmittance for standard light source A, but infrared light This also resulted in an increase in energy and UV transmittance. Therefore, automobile manufacturers To compensate, mosquitoes are increasing the size of their air conditioners to handle a larger heat load. Interior fabrics and internal plastics to prevent deterioration due to ultraviolet rays. I ended up having to put UV stabilizer into the parts.

The glass composition according to the present invention, when manufactured to a thickness of about 3 mm to 5 mm, has a It exhibits a visible light transmittance of at least 70% by light source A, making it a highly desirable infrared energy source. It has a combination of UV transmittance and UV transmittance. Glass set according to the invention The total solar energy transmittance of the composition is at glass thickness between 3 mm and 5 mm. , about 46% or less.

Preferably, the total solar energy transmission at these thicknesses is about 45% or less. be. Total solar energy transmittance is the transmittance of solar energy over the entire wavelength of solar energy. It is a measure of energy transmittance for visible, infrared, and ultraviolet energy wavelengths. This is the integral value corresponding to the lower region of the wavelength versus transmittance curve. The gas according to the present invention The UV transmittance of the glass composition is about 3 at glass thicknesses between 3 mm and 5 mm. 8% or less, usually about 36% or less. UV transmittance is 300nm and 40nm It is an integral value representing the area under the wavelength versus transmittance curve at wavelengths between 0 nm. Current As will be understood by those skilled in the art, the scope of the glass composition according to the invention as described above includes: It is adjusted to provide the desired properties at a particular desired thickness.

Suitable batch materials according to the invention include sand, limestone, dolomite, soda ash, mirabilite, stone Contains titanium compounds such as plaster, red pepper, charcoal, and titanium dioxide; Mixed by glass batch raw material mixing equipment. Here, important implementations of the invention By way of example, surprisingly, the use of titanite as a source of titanium is particularly advantageous. It is advantageous that not only titanium dioxide but also at least a part of Fe20m is supplied. Ru.

These batch materials are conveniently mixed and melted in a conventional glassmaking furnace and A neutral, usually green, infrared energy and ultraviolet absorbing glass composition made of This is followed by a continuous float glass process to create a molten metal bath. l bath). The manufactured flat glass is molded into architectural window materials. by cutting, cutting or forming, e.g. by press bending. It is used as a window material for automobiles.

As mentioned above, the mineral titanite, i.e. titanium oxide (Hv) iron (II) (Fe TiOs) is used as a raw material for glass batches, including titania (diacid) of pigment class quality. It has several advantages over titanium chloride (Ti0z). Especially regarding handling While titanite exists naturally as crushed sand-like crystal grains, Tania is an expensive artificial fine powder. Titanite crystal grains are freed by gravity , and has almost the same angle of repose as quartz sand. The particle size of titanite is different from that of other Because the particle size is the same as the glass batch raw material, it can be used in a wet batch mixer. Can be homogenized well and does not separate. Fine titania powder has a similar effect to van der Waals forces. It does not flow freely due to the intermolecular bonding force. The problem of separation and homogenization is with titania powder. This is caused by the size being too different from other glass batch raw materials. Ru. It is difficult to weigh or transfer fine powder in the weighing room, and This results in variations in the chemical quality of the produced glass. Mix well Failure to do so may result in glass quality problems and increase variations in the chemical quality of the glass. make it big Furthermore, the use of titanite is advantageous from the viewpoint of melting and chemical action. There is a point. The crystal grains of titanite are black and easily absorb heat. Melts easily. Titania powder is white and reflects heat easily, so it is difficult to melt. requires more energy. Titania powder may have poor mixability or flow easily. If it becomes a lump due to the problem of heat, it becomes more difficult to melt.

The presence of oxides in the reduced state increases the stability of the molten glass and also It is also related to improving the quality of lath. Titanite usually contains up to 50% FeO. It promotes the reduction of the molten glass and controls the optical properties of the glass. current Currently, carbon is used to control the oxidation state of glass. Titanite is in an oxidized state due to which it is very stable at high temperatures. carbon is converted is converted into carbon dioxide, and the iron and titanium present in titanite are directly transformed into gas. The melt penetrates into the glass and does not cause any volatilization.

The composition of the fused and cast soda lime silica glass according to the present invention is as follows: is: A) about 65% to about 80% SiO2 by weight; B) about 10% to about 20% by weight Na2O: C) about 1% to about 10% by weight; D) about 1% to about 10% by weight % MgO by weight.

E) about 5% to about 15% by weight Cab; F) about 0% to about 5% by weight Al2 O5; G) About 0% to about 5% by weight Bad; H) About 014% to about 0.9% by weight Amount% of F e s Oa;■) About 0.1 wt % to about 0.5 ffi Amount % of F e 0% The weight percent value of this Feo is the reduction rate of the entire iron contained in the batch (first 19% to at most 50%; ■) T i O* of about 0.25% to about 1.25% by weight.

More preferably, it is important that the glass composition obtained contains: A) about 70% to about 74% by weight SiO*; B) about 12% to about 14% by weight Nano: C) about O wt % to about 1 wt % KtO; D) about 3 wt % to about 4 wt % % MgO; E) about 6% to about 10% CaO; F) about 0% to about 2% by weight % Altos; G) from about 0.45% to about 0.45% by weight; 9% by weight of Fe1on;H ) approx. 0. 1% by weight to about 0.3% by weight of FeO, the weight percent of this Feo The iron value indicates that the reduction rate (iron oxide value) of the entire iron contained in the batch is about 20% to at most 29%; ■) About 0.25% to about 1% by weight of TiOz, this glass has very little remaining Besides the amount of melting accelerator and/or impurities that have no effect on the properties of the glass Contains nothing that affects this glass.

If the nominal glass thickness is 4 mm, the Fe2on content in this glass is approximately 01 6ffi% to about 0.9% by weight.

The glass matrix is formed by quartz. Sodium oxide, potassium oxalate and calcium oxide act as a fluxing agent to lower the melting point of the glass. Alumina is Adjusts the viscosity of glass and prevents divitrification. ingredient. Additionally, magnesium oxide, calcium oxide, and alumina work together to form glass. Improve durability. Glauber's salt and gypsum act as purifying agents, and carbon is known as a reducing agent. It is.

Iron is typically added as iron or Fe2Om, but preferably in small amounts. At least some of it is added as titanite, and some of it is reduced to FeO. It is desirable that The total amount of iron in the batch is highly influential and is expressed as Fe20m. The weight percentage added should be from about 0.45% to about 1% by weight. Approximately 0.6 weight % to 1.0% by weight is more preferable. Similarly, the degree of reduction, i.e. - Iron oxide value is important and should be between 19% and 50%, 20% and 2 More preferably, it is between 9%. The overall iron concentration range mentioned above, or the secondary oxide According to the range of degrees of reduction of iron to ferrous oxide, the resulting glass is about 0. 4% by weight to about 0. 9% by weight Fears and about 61% by weight to about 0. It will contain 5% by weight of FeO.

If the amount of iron reduced is greater than the above amount, the color of the glass will be too dark and light source A will Therefore, the visible light emission rate becomes lower than 70%. Furthermore, FeO increases and prevents heat from penetrating into the interior, making it more difficult to melt the glass batch. . If the amount of iron reduced is less than the amount mentioned above, or if the total amount of iron used is For a smaller amount of , the total solar energy transmission through a glass of desired thickness is It exceeds about 46%. If the total amount of iron is more than the above amount, the internal Less heat penetrates and melting of the glass batch becomes more difficult.

Furthermore, the concentration of titanium oxide, which works with iron to absorb ultraviolet rays, determines the balance of transmission characteristics. have a major impact on the

The concentration of titanium oxide is approximately 0. Must be 25ffiflt% to about 1.25% by weight but especially from about 0.25% to about 1.5% by weight. It is preferably 0% by weight, and More preferably, it is about 0.4% by weight to about 0.9% by weight. Chi oxide As the concentration of tan increases, the color of the glass gradually changes towards yellow-green, making it more popular for sale. The color ends up being unacceptable for sales. If the concentration of titanium oxide is too low, it will turn purple. The transmittance of external rays becomes unacceptably high.

As is understood, the concentration of important iron and titanium oxides is limited, and Fezes By interacting, the reduction rate to FeO is adjusted to the desired degree. neutral, usually green, visible light transmittance from light source A is higher than 70%, full thickness It is more preferable that the transmittance of positive energy is about 46% or less and the ultraviolet transmittance is about 38% or less. Preferably, a glass composition is produced that is 36% or less.

Furthermore, the glass according to the invention has a dominant wavelength of about 498 to about 535 nm by light source C. and exhibits a color purity of about 2% to about 5%. Most of them are about 2% ~4%. The color purity of automotive window materials is an important variable and should be as small as possible Preferably a value. For comparison, blue glass has a color purity of approximately 1 It reaches up to 0% and is therefore undesirable as a window material for automobiles. Changes other than color purity In numerical terms, the color of the glass according to the invention is defined by the CIELAB system: It is expressed as follows using the variables. a*=-10+10; b”=4±5; L= 89±100 further a 11 ==8±4, b”=2+3/-2, L=89 A typical soda-lime-silica glass batch feedstock according to the present invention to be ±2 with a reducing agent such as red iron, carbon, and a titanium compound such as titanite. A 4 mm thick test sample was produced by mixing together and further melting. . The obtained glass sample showed the following characteristics: (See the margin below) The complete composition of the glass of Example 4 is as follows (% by weight): 5i02=73. O ;Na! 0=13,9; Ca0=7°8; Mg0=3.4; Fe*0s=0,7 67; TiO*=0゜654; A lso=o, 345; K*O=0 ．． 08° The composition of the glass batch of Example 7 is (parts by weight) t)): sand = 145; limestone = 11; dolomite = 33, soda ash = 50, gypsum = 1 , red iron = 0°67, titanoferrite = 2.25, and charcoal = 0.05. obtained The complete composition of the glass was as follows (% by weight): S 102 = 73. 25; Fe*Om=0.697; Att.

,=0. 168; TiO*=0. 70; Ca0=7. 786; Mg0=3 ．． 44; NatO=13.92; KzO=0°038° Although the invention has been described with reference to specific examples, those skilled in the art will appreciate that Various modifications and changes may be made without departing from the scope of the invention as defined below. It is.

Continuation of front page (81) Designated countries EP (AT, BE, CH, DE.

DK, ES, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE ), 0A (BP, BJ, CF, CG, CI, CNi, GA, GN, ~i L, MR, NE, SN.

TD, TG), AT, AU, BB, BG, BR, BY.

CA, CH, CN, CZ, DE, DK, ES, FI, GB, GE , HU, JP, KG, KP, KR, KZ, LK, LU, LV, MD, MG , MN, MW, NL, No.

NZ, PL, PT, R○, RU, SD, SE, SI, SK, TJ, TT, UA ,UZ,VN (72) Inventor: Paker, Rodney Gee 4353, Ohio, USA 7. Maumee East William Street 605 (72) Inventor Cheno , Joseph G., Perrysburg, Ohio 43551, United States Est South Boundary Street 309

Claims (1)

[Claims] 1. A neutral, usually green, soda-lime-silica glass composition containing from about 0.4% to about 0.9% by weight Fe2O3 and from about 0.1% to about 0.9% by weight. 5 wt.% FeO and about 0.25 wt.% to 1.25 wt.% TiO2; The visible light transmittance by light source A is higher than 70%, and the transmittance of total solar energy is approximately 46% or less, and furthermore, the transmittance of ultraviolet rays is about 38% or less. glass composition. 2. Claim 1, characterized in that it has a color defined by the following CIELAB values: Glass composition as described: a''=-10 10; b''=4±5; L=89 Sat 10. 3. The weight percent of FeO is expressed as Fe2O3, and the reduction rate of the entire iron is about 19%. Glass composition according to claim 1, characterized in that it represents at most 50% thing. 4. about 0.45% to about 0.9% by weight Fe2O3 and about 0.1% to about 0% by weight ．． 3 wt.% FeO and about 0.25 wt.% to about 1 wt.% TiO2. The glass composition according to claim 1, characterized in that: 5. from about 0.6% to about 0.9% by weight Fe2O3 and from about 0.1% to about 0.9% by weight. 3% by weight FeO and about 0.4% to about 0.9% by weight TIO2. The glass composition according to claim 4, characterized in that: 6. The weight percent of FeO is expressed as Fe2O3, and the reduction rate of the entire iron is about 20%. 5. A glass composition according to claim 4, characterized in that it represents about 29%. 7. Claim 4, characterized in that it has a color defined by the following CIELAB values: Glass composition as described: a''=-8 4; b''=23/12; L=89±2. 8. A neutral, usually green, soda-lime-silica glass composition containing and about 0.4% to about 0.9% by weight of Fe2O3 and 0.1% to about 0% by weight of the ladle. ．． 5 wt.% FeO and about 0.25 wt.% to 1.25 wt.% TiO2. , At a thickness between about 3 mm and about 5 mm, the visible light transmittance by light source A is 70 %, the transmittance of total solar energy is about 46% or less, and the ultraviolet rays A glass composition having a transmittance of about 38% or less. 9. A neutral, usually green, soda-lime-silica glass composition containing and about 0.6% to about 0.9% by weight Fe2O3 and about 0.1% to about 0% by weight. ．． 3 wt.% FeO and about 0.4 wt.% to about 0.9 wt.% TiO2; At a nominal thickness of 4 mm, the visible light transmittance by light source A is higher than 70%; The transmittance of total solar energy is about 46% or less, and the transmittance of ultraviolet rays is about 46% or less. A glass composition characterized in that it is 38% or less. 10. The weight percent of FeO is expressed as Fe2O3, and the reduction rate of the entire iron is about 20%. 10. The glass composition of claim 9, wherein the glass composition represents approximately 29% of the glass composition. 11. At a nominal thickness of 4 mm, the total solar energy transmittance is approximately 45% or less. A claim further characterized in that the transmittance of ultraviolet rays is about 36% or less. 10. The glass composition according to 10. 12. A neutral, usually green, soda-lime-silica glass composition, the base of which is The glass contains 65% to 80% by weight of SiO2 and 10% to 20% by weight. % of Na2O and 5% to 15% of CaO by weight, 1% to 10% by weight of MgO; 0% to 5% by weight of Al2O3; 0% to 10% by weight of K2O, 0% to 5% by weight of BaO, and even a very small amount of melt accelerator. and a purification accelerator; 0.4% to 0.9% by weight of Fe2O3 and 0.1% to 0.5% by weight of F Contains eO and 0.25% to 1.25% by weight of TiO2 as main components including a coloring agent, At a nominal thickness of 3 mm to 5 mm, the visible light transmittance by light source A is 70 %, the transmittance of total solar energy is about 46% or less, and the ultraviolet rays A glass composition having a transmittance of about 38% or less. 13. A neutral, usually green, soda-lime-silica glass composition, the base of which is The glass contains 70% to 74% by weight of SiO2 and 12% to 14% by weight. % of Na2O, and 6% to 10% of CaO, 3% to 4% by weight of MgO and 0% to 2% by weight of Al2O3; Contains 0% by weight to 1% by weight of K2O, and further contains a very small amount of melting accelerator, if any. and a purification accelerator; 0.45% to 0.9% by weight of Fe2O3 and 0.1% to 0.3% by weight Coloring containing FeO and 0.25% to 1% by weight of TiO2 as main components containing an agent, At a nominal thickness of 3 mm to 5 mm, the visible light transmittance by light source A is 70 %, the transmittance of total solar energy is about 46% or less, and the ultraviolet rays A glass composition having a transmittance of about 38% or less. 14. A neutral, usually green ultraviolet-absorbing soda containing iron oxide and titanium oxide A method of manufacturing a lime-silica glass composition, the method comprising: Sulfate selected from the group consisting of Glauber's salt and gypsum, sand, soda ash, and dolomite Including the process of mixing, heating, and melting stone and limestone, Furthermore, as a source of the titanium oxide, and iron oxide contained in the obtained glass, including titanite in said batch as at least part of the source. A method for producing a glass composition, characterized in that: 15. Claim characterized in that the titanite contains up to 50% FeO. 15. The method for producing a glass composition according to 14.